1. Technical Field
Embodiments generally relate to power management for devices of a computer platform. More particularly, certain embodiments provide for a method tying a processor power state transition on a platform to another power state transition of the platform.
2. Background Art
In existing computer platforms, operating systems (OS) variously support power management techniques which are specific to a particular processor—e.g. with traditional Advanced Configuration and Power Interface (ACPI)-based mechanisms. For example, current OS power management (OSPM) mechanisms provide for transitioning a platform processor core to a processor-specific, idle processor power state such as a C6 power state.
The introduction of autonomous device power management has allowed such computer platforms to increasingly rely on drivers for various types of devices that independently manage transitions between device-specific power states, each for their own respective platform device.
However, to date, the transitioning of a platform's processor to a particular processor-specific power state has been independent of any transitioning of other types of devices of the platform to their respective device-specific power states. For example, existing OS power management (OSPM) mechanisms do not to facilitate any correlating of a processor power state transition to another power state transition on the platform, where the other power state transition is specific to, or inclusive of, transitioning power state of another—e.g. non-processor—type of platform device.
By relying on separate power management determinations and their corresponding separate platform state transitions—e.g. a processor-specific power state transition and a separate (extra-processor) device power state transition—existing computer platform power management techniques fail to account for possible opportunities to avail of more efficient power states from the perspective of the computer platform as a whole.